JSON-DATA: Display input in the com_ back-end and save data in the DB

Question

I'm developing my custom component for storing some records in the DB. In my #__records DB table there is the column attribs where I want to store some data in json-format like:

{"field1":"value1","field2":"value2"}

I try to add the input for the field1 in my admin/models/forms/record.xml like:

<fields name="attribs">
  <fieldset name="basic">
     <field name="field1" type="text" />
  </fieldset>
</fields>

and I can render it in my admin/views/record/tmpl/default.php via foreach:

<?php foreach($this->form->getFieldset() as $field): ?>
    <?php echo $field->input; ?>
<?php endforeach; ?>

Although at that the field1 hasn't its value that is already stored in the DB.

There are two questions:

1. How can I render the input in views/record/tmpl/default.php not via foreach but like:

echo $this->form->getInput('field1'); // it doesn't display the input at all

and with its stored value

2. How can I save new value of the field1 i.e. what code should I add to the save($data) function in my admin/models/record.php (or to JTable class)? I need something like:

public function save($data)
{
   if(isset($data['attribs']) && isset($data['attribs']['field1']))
   {
      // what code should be here ???
   }
   return parent::save($data);
}

Answer 1

Please see following answers to your question:

You can render individual field as follows:

echo $this->form->getField('field1')->label;
echo $this->form->getField('field1')->input;

At this time you would not have a value to above input field. If you want to give default value to your field1 then you can do following in your model:

Make sure that you are extending your model with JModelForm or JModelAdmin

override getForm method

public function getForm($data = array(), $loadData = true)
{
        $form = $this->loadForm('com_yourcomponent.formname', 'formname', array('control' => 'jform', 'load_data' => $loadData));

  if (empty($form))
  {
      return false;
  }            

  $form->setFieldAttribute('field1', 'default', 'Your Value');

  return $form;
}

If you want to get value in runtime them do following:

In your save($data) method of Model

public function save($data)
{
   // Get the value of field1 with it's name. Make sure to check if value exists.
   $field1 = $data['field1'];
   $field2 = $data['field2'];

   // Merge both field's value to one Array
   $attribs = array('field1' => $field1, 'field2' => $field2);

   // Convert it to JSON object
   $data['attribs'] = json_encode($attribs);
   return parent::save($data);
}

Answer 2

Ok, yet I resolved the first issue with the code:

$json = $this->item->attribs;
$obj = json_decode($json);
$value1 = $obj->{"field1"};
echo $this->form->getField('field1','attribs')->label;
echo '<input type="text" name="jform[attribs][field1]" id="jform_attribs_field1" value="'.$value1.'" class="inputbox" size="40" />';

and to the save($data) function in the model I've added only the code:

$attribs = array();
$attribs['field1'] = $data['attribs']['field1'];
$data['attribs'] = json_encode($attribs);

There is no need to add something to getForm method

Now everything works perfectly but any better solution would be appreciated